Many modern vehicles include one or more sensors for evaluating the local environment around them. Many vehicles also communicate with other vehicles using vehicle-to-vehicle (V2V) methods. In V2V systems, vehicles exchange messages including operational parameters such as location and kinematical details (e.g., velocity). Primary benefits of such sensor and V2V systems include safety and facilitation of driving.
For example, the computer of a first vehicle can advise the driver that another vehicle is positioned in its blind spot. The computer may have received data about the neighboring vehicle from the vehicle sensors and/or from a V2V message from the other vehicle. The other vehicle could also communicate to the first vehicle that it is accelerating or decelerating, planning to switch lanes away from the first vehicle (e.g., turn blinker initiated), etc.
Due to the importance of the information shared in V2V systems, transmissions are secured. One way of securing wireless communications is by using a Broadcast Authentication Scheme (BAS). BASs for vehicular wireless networks enable secure transmission and receipt of messages between vehicles. BAS, though, at least intermittently occupy a relatively large amount of limited vehicle computing resources.
One drawback of BAS is time delay between initial transmission of a message from the broadcasting vehicle and authentication of the messages at the receiving vehicles. During the delay, vehicle location and movements change, rendering the message less reliable. Also, the strain placed on vehicle computers for BAS computations increase sometimes leading to packet loss and increased system vulnerability, such as to denial-of-service (DoS) attacks.